Designing DB partitions you don't have to babysit

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• Hacker News
• Or just use kdb+ and 1bn rows a day is par for the course.
  by leprechaun1066
• For anyone interested in the topic I suggest reading about snowflake id [https://en.wikipedia.org/wiki/Snowflake_ID] or uuid7 the patterns from the article translate cleanly. The bigint is 64 bytes where uuid is 128. There are other caveats but its all about tradeoffs.
  by piterrro
• Technically - as Postgresql stores the UUID data type as binary, it's 16 bytes.
  by khurs
• Or you could just warehouse the daily data into something like ClickHouse and start fresh every day. It's built for this kind of workload and has demonstrated some absolutely insane analytical performance at massive scale. We're currently running it on an $170/month VPS, querying over 500+ billion rows daily without any issues. At that point, partitioning an ever-growing OLTP table starts looking like the harder problem.
  by djfobbz
• With the other comment about kdb+ and this show a misread of the article: The article AND ANY use of a columnar DB show the same issue: Point lookups are badly pessimized with both partitions on other columns and/or columnar.

  That is why columnar DBs, not matter how impressive, are not used by OLTP workloads (and here this article point you can undo the advantages without pay attention at the consequences of partitions).

  by mamcx

•   The application probably still treats id as unique, but nothing in the schema guarantees it. And you can’t recover the guarantee with a separate UNIQUE (id) constraint: both MySQL and PostgreSQL require every unique constraint on a partitioned table to include the partition key columns. The uniqueness property has effectively been traded away.
  

  Not really?

  MySQL has AUTO_INCREMENT [1]

  PostgreSQL has SERIAL [2] and CREATE SEQUENCE [3]

  What am I missing?

  [1] https://dev.mysql.com/doc/refman/8.4/en/example-auto-increme...

  [2] https://www.postgresql.org/docs/18/datatype-numeric.html#DAT...

  [3] https://www.postgresql.org/docs/18/sql-createsequence.html

  by Insimwytim
• And the post did mention it, argueing it may be better to partition by auto-incremented ID with the support of catch-all range and partution monitoring.

  > The primary key already exists. For tables using BIGINT AUTO_INCREMENT, it’s monotonically increasing: newer rows have larger IDs. That’s the property range partitioning needs. The primary key is the partition key.

  by toledocavani
• This is a topic that interests me a lot but there's a lot I find surprising since I finally started working with postgres dependent apps. Why for example is the id a good primary key? Joins are not uncommon, but I don't have anyone searching on id in my application and it is not even supposed to be user visible. I would think every possible user search would look at all partitions indexes if I did this instead of creation date.
  by yasaheblasa
• Your primary key is there to uniquely identify a record. You need additional indexes on fields you will search on.
  by jagged-chisel
• Allow me to clarify a bit more.

  You “search” for a record (perhaps based on username [and then you verify the password hash, but I digress]) and now you know the ID. Carry the ID in a session (the app doesn’t display this) and you can modify this specific user’s record. This is especially useful if you allow editing fields on which searches happen. Want to change a username? Great, you can.

  If the username is your primary key, and you allow users to change them, there are edge cases and nuances and headaches … just use something immutable to identify records - autoincremented int, UUID, etc

  by jagged-chisel